(1) Field of the Invention
The invention relates to composition of swollen silicone polymer, process for making the same and personal care formulations using the same.
(2) Description of Related Art
The personal care industry thrives on being able to deliver multiple performance products based on mixtures of several components, with each component having a performance and compatibility profile, which can lend that component to properties that are important to or desirable in certain final product formulations. One desirable property is the ability to provide a silky initial feel. This property can be derived from the use of cyclic siloxanes in the formulation. In addition to the silky initial feel, cyclic siloxanes used in silicone gels can simultaneously maintain a high viscosity product, which can also be desirable for various product formulations. Although cyclic siloxanes provide the desired feel characteristics, they are low viscosity, highly flowable liquids. Thus, they are not easily held in a formulation, preferring rather to separate and flow out of a given container or flow uncontrollably across the skin when used in a specific application. Further desirable properties include achieving an initial silky feel while providing a smooth, low-residue feel upon dry-down, as well as achieving a high transfer resistance in as short a period as possible.
Cyclic siloxanes have limitations in terms of their performance and compatibility profile. A desired performance and/or compatibility profile possessing the various desirable properties described above is not always achievable by using a cyclic siloxane. Certain applications can require a different performance and/or compatibility profile that cannot be met by the use of cyclic siloxanes.
In addition to providing a particular performance and/or compatibility profile, cyclic siloxanes provide effective swelling of silicone polymer networks. In addition to cyclic siloxanes, linear siloxane fluids have been used to swell silicone polymer networks and to provide a different performance and/or compatibility profile and different end application benefits from that of cyclic siloxanes. These linear siloxane fluids are made via an equilibrium process and comprise a distribution of molecular weights. Unfortunately, up to now, the use of linear siloxanes has required a much higher level of silicone polymer network (solids) to obtain the desired viscosities that are obtainable through cyclic siloxanes. Using higher amounts of solids has processing and cost disadvantages. In addition, using higher amounts of solids can cause “balling” of a product on the skin, which is a negative sensory attribute.